Linkage connector



c. JOHNSON 2,615,738

LINKAGE CONNECTOR Filed March 18, 1950 Oct. 28, 1952 MATERIAL INVEN TOR.

CLARENCE JOHNSON NON MAGNETIC Patented Oct. 28, 1952 L LINKAGE CONNECTOR. Clarence FJohnson fSouth Euclid, Ohio; assign:

to 'iBaiiley ,rJMetemGomp (Delaware any, :a .corporationpof v;A p 1flioar,tion'liiarch'fl8, 195.0, 'SeriafNo. 15 1365 :My invention "lies "generally in :themeld' of con- -nections and "couplings. More particularly-my "invention-mas application in the numerous :mechanicallinkage-systems in which simplicity of eiement -j'oin'der is desired, 'coupled -*with case of di sjo'inderfor-adjustment and disassem'bly pur- 130888.,"3116 particularly related to -instrument linkages.

.}."*AS the present problem is--stpproacl 1ed there canbe seen at -'-1east"three paramount objectives -cto be atta'ined in mechanically-coupling driving -and driven li'nkagemembers. It is-first seen-that the junction means must v:ailow ea. desirable latitude "of 1 angular movement between the joined ":members,'-second, theremust be o. minimum :of {friction and "binding whieh would promote lnystere'si's in the system operation and fina'zllyythe structure'must-be simple {routine-standpoint of daci-iitating manufactureand :assembly.

- "Every connection-or coupling in a system of linkage is vitally important per -seandpas their 1 member in even the simpler 'systems is otten I numericallylarge the-attainment ot'all the-parac mount advantages :outiined supra as necessary. i' isomewhat auxiliary ere --those des'irablea struc :turol"features-which promoteifreedomfiromvi- I ;-:braationa'i eflects freedom 'trom' feulty -opera'tion )dueto dirt and foreign materiall, andmo's'itivein- 'dication of misalignment or defective-coupling.

- mea-ns of comparing the present invention with the prior 'art-mests "in-the well known'struw ture-.- for joining driven and driving -*members "whioh is descriptively referred toas' the pi-n and clip combination. A pin, integrztl with --'perha. ps the driving member and 90 to the-plane of-eoti- Wation, may =be==inser ted through-4e. hole-in the driven:rnem'ber ande. :pivoted clip on the driving :merriberswung over-the Jtoprof the pinto guard against. disengagement.

it is perhaps obvious -wherein 1ie the'1imita. ,tions :ofithe pin and .clip combination. 'Therexis,

' of course,v danger-that an zinexperiencedopemtor 'williai'l :to detect: :a. :bent tpinuor {or loose :clip,

binding and vproducing;friction and causing' possible disengagement. It is to overcomeithe' lim'itations :and .-complications attendant "the -pin-imd .clip combinations and v ssirn'liar mechanical connectionsithat the present invention was devised.

'It'viS :a-n object of my "invention to prov ide av means =of..coupling two operative flinkage mom- -bers together through a structure which willel flow unrestricted rotation in .-a,- --=ple-ne, o! either 7 emen'iber,r-etbout therpivotalvstrueture;

:Itflis another object of: my invention to-prowhich may 'be' d-isconnected by a singie operait'or' originated mOVemen'tmI either'of the mm. i

"It is a further 1 object tot my invention 'to areduce-danger-of couplingmisalignment and render a, positive 'indication ashould -misalignmm'it occur.

Another object of my invention provide =a--coupling pivot upon whic'hdirt and matter have a minimum-detrimental 'efiect;

fit is another object woi' my invention to vide-a.pivota1coupling which is'rsimpleio'f-manutacture andzassemblyr "Fig. '1 is 'a-"linkage' system embodying-entwin- :vention.

"is-.2. *deliall'lm'f Mesa. I Jig- 4" is another-embodimentxii -the detain- 6! @Fig. :3.

5 isanotherzembodimerit-01. lthedetaiil e y Fig.'i3.' 1

:Fig. e'fifiis: .another-;-embodiment orf the netdii -of .fliiswanothjer embodimentqofthe detail 'of Fig.3;

In Fig. 1 I have disclosed a. system of linkage bynmeans of which etwo rvariables .sare iinterre- :lated into a value whioh maybe expressed moon 2. chart. It ids-notdeemedmecessary to elaborate upon the theory ofvarieble production. interrelatedfiby .the linkegexsystem. It is-sumdient that a device is indicated, responsivelto tie-l pressures applied t-hrough pipes l-end -position'ing a :mem'berl in-accordance with-m ditfiferential pressure relation;

In accordance with a-second variable, {*Boiirdon tubei' is positioned by Dressu'res'iin pipe i tmiin I turn, position a member =1 ofthe linkage "-isystem -inzaccordance with the magnitude ofthe-varieble Fromthe foregoing it can "be readily-seen that with two 1 variables i determining the position of wide ::a .:coupling between :-two iinkage members 1:

members -in 'the d-isolosedl-inkage systemf'pointer 8 is mechanically positioned'relative tochart 1:8 for. indicating and/'orrecording the-weloitionebe tween the-"variables.

Asrth'e various membersof the linkagerrsystem, connected and between members I and! "and -;poi'nter i8, position-"to give final indications-on chart 9. they -=pivo,t--about points -10, H, 12', fit :.-and; l-l. inacoordance 'with previously 'obiec'tives it is desirable -that-' these;pivots rajllow :suificient angina-r movement "throughout their predetermined range, impart no friction-townie system-and yet-remain of .the simplest'npossible =constmictionin.tbeircmanufacturerend essembiy.

"Fig. :2 is an enlargedacross-sectional?detail- 5o! the system of Fig. 1, I show member 2| driving,v

or being driven, by member 22 and pivoted withdrawal of the pin shaft from a hole, or a recess, in a member 26. Member 26 is generally similar in shape to member 25 and is rigidly connected to link member 22. The hole, or recess, in member 26 accommodating the tapered portion of the pin shaft is centrally located in member 26, and is deep enough, or the pin shaft is short enough, to allow members 25 and 26 to present flat surfaces to one another. With a means of bonding 25 and 26 together, the combination of pin 24, members 25 and 26 and link member 22 become a unit about which link 2| through the structure of my invention. Member 2| is provided with a hole 23 near one end and in which is placed the shaft of headed pin 24. The hole 23 provides the bearing surface of the pivot. The diameter must be just enough in excess of the pin shaft diameter to allow member 2| to rotate with a minimum of friction and yet introduceno undesirable. looseness or play. The limits of .the amount of play at this point in the structure would be a factor of the service required of the linkagesystem and therefore falls into the realm of design of the individual application. a The head of pin 24 need only be sufficiently largeto retain member 2| on the shaft. The bearing of the head on link 2| is reduced to line contact by tapering the inside head surface from the pin shank to the perimeter of the head. With the head surface, tapered in the manner disclosed, coming intocontact with the link member 2 I, friction is reduced to a minimum during the'normal activation of the link about the shaft in a two dimensional'plane and not increased materially should a degree of misalignment be introduced. Varying the degree of head inner-surface taper of the pin will vary the amount of friction with link 2| should it vary from a true 90 alignment with the pin shaft. Anticipated member 2| and pin shaft alignment variation will determine the optimum degree of 'pin head taper and from this point of disclosure the structure again falls into the realm of design. I The 'pinshaft, from the head, is of uniform diameter for a length sufllcient to accommodate member 25 disclosed here to be of the same diameter and generally cylindrical shape as is the pin'head itself. As willbe disclosed hereinafter, .the shape of this member 25 may be varied in certain dimensions but is always provided with a centrally located hole which press-fits on the pin shaft. The pin head link 2| and member 25 are then aligned along the pin shaft close enough together to reduce the side motion allowance of link 2| to a desired minimum. The surface of member 25 adjacent link 2| is given a taper from its hole outward after the manner of that taper of the head of pin 24, and captured link plished-in the heretofore disclosed pin .and clip combination.

It is seen that the'pin shaft beyond member 25 is given a taper to allow ease of insertion and can rotate in the function heretofore described.

To bond members 25 and 26 together I have magnetized either 25 or 26, or both. With 25 or 26, or both, magnets, my pivotal structure may be simply and positively formed by inserting the tapered portion of the pin shaft in member 26 until the magnetic lines of flux bond 25 and 26 together into a unit. To disassemble my pivot structure, an operator need only overcome the magnetic force by a direct pull which separates 25 and 26. The strength of the magnetic force is governed by sizing and shaping permanent magnets 25 and/or 26. Thedesign of permanent magnets is accomplished in general by empirical methods and I will suggest hereinafter only some of the general shapes that may be given magnets adapted for use in my invention.

In Fig. 3 I show magnetic members 25 and 26 with a pole uniformly distributed over the flat surface of each magnet, the opposed faces of 25 and 26 being given poles of opposite polarity. However, magnetizing only one of the members will produce a relatively weaker bond between 25 and 26 which will have to be accounted for in design. 7

A method of increasing the magnetic strength of the magnet shapes of Fig. 2 and Fig. 3 is illustrated in Fig. 4. A channel is made across the face of either, or both, magnets 25 and 26 and a face contains both poles. This will produce magnets more similar to the conventional horseshoe type rather than the bar type of Fig. 3 with consequent strength increase in accordance with established principles of both types. Of course, possible repulsion of like poles can be avoided by magnetizing only one of the magnets as suggested supra.

Another means of'strengthening the pole attraction may be accomplished by lengthening the-distance between poles of the bar type of Fig.3 by giving the magnets an elliptical shape as disclosed in Fig. 5.

Still another means of gaining permanent magnet strength is expressed in Fig. 6 where I have shown a well known commercial magnetic assembly by means of which high magnetic strength is derived from relatively small assemblyof parts. The assembly utilizes the "shunt method of magnetic concentration. A flux field of a cylindrical magnet is passed through two conductingpaths to a small air gap, or equivalent, between them and around which the field concentrates. I

For its size, this magnetic structure has great strength, and with one of the links mounted with a structure of this nature and the other carrying a soft iron member, a pivot can be made of practical strength, and size can be kept within reasonable'limits.

Referring now to Fig. 7, I have shown'a choice of structure which was heretofore indicated as a possible modification of Fig. 3. Actually, Fig. 7 is a compromise between Figs. 3 and 4' in that one of the bodies, or 26, is channeled to form a horse-shoe type of magnet while the unchanneled body is not magnetized at all but is attracted to the magnetic body to bond both bodies together. The unchanneled body should be of easily magnetized material and low retentivity, such as the soft irons.

While I have chosen'to illustrate and describe certain advantageous embodiments of my invention. it will be understood that this it by way of example only and I am not to be limited thereto.

What I claim as new and desire to secure by Letters Patent of the United States, is:

1. A pivot connection between two members of a linkage system including, a driven member having a hole therethrough, a pin free to rotate in the hole of the driven member, a magnetized first body connected to said pin with said driven member restrained between the pin head and said body, a driving member, and a magnetized second body connected to the driving member and having a hole accommodating the pin.

2. The pivot connection of claim 1 in which one of the bodies is of a material readily magnetized and of low retentivity while the other is a permanent magnet.

3. In a system of linkage having driving and driven members, a driving member with an aperture therethrough, a headed pin adapted to rotate freely in the aperture of said driving member, a first permanent magnet connected rigidly to said pin capturing the driving member between itself and the pin head and having a channel through the center of the face away from said pin head and captured driving member, a driven member, and a second permanent magnet similar to the first magnet connected to said driven member and having a recess for accommodating so much of the pin as will allow contact between the magnet faces.

4. In a magnetic coupling between a driven and driving linkage, a pin member accommodated within an aperture of a first linkage member freely enough to rotate with a minimum of friction, a head on said pin member with its face adjacent the accommodating link tapered from its center to its perimeter, a first magnetic body connected to said pin capturing said link between itself and said pin head and having that face of it adjacent said link tapered from its center to its outer edge elongated in an elliptical shape to lengthen the flux path between the poles, and a second magnetic body connected to a second linkage member and of a shape assumed by the magnetic first body and accommodating the pin length necessary to allow contact between the flat surfaces of the two magnetic bodies.

5. The magnetic coupling of claim 4 in which one of the magnetic bodies is of a readily magnetizable material and the other body is permanently magnetized.

6. In a magnetic coupling between a driven and driving linkage, a pin member with a single head tapering from the pin shank to the head edge, means of accommodation in one of said linkages which will allow free rotation of the pin shank, a soft iron wafer-member tapered in manner similar to that of the pin head and pressed solidly on said pin shank to retain the accommodating link with said tapered pin head, and a permanent magnet structure connected to the other of said linkages including two shells of magnetic material concentric and connected through a cylindrical magnet whose flux is conducted by the shells to their adjacent edges separated by a small air gap equivalent and aligned for contact with the face of the soft iron wafermember by the pin shank.

'7. In a magnetic coupling, a first linkage member with an aperture therethrough, a second linkage member, a pin member accommodated within the aperture of the first linkage member and sized to rotate therein with a minimum of friction, a head on said pin member with its connected face tapered from the connected pin to its outer edge, a first cylindrical magnetic body connected to the pin member so as to capture the first linkage member between the head and a body face tapered from the center of the face to its perimeter, and a second cylindrical magnetic body connected to the second linkage member with an aperture therethrough accommodating so much of the pin as will allow contact between the two magnetic bodies.

8. The magnetic coupling of claim 7 in which one of the magnetic bodies is of a readily magnetizable material and the other body is permanently magnetized.

9. In a system of linkage having driving and driven members, a driving member with an aperture therethrough, a headed pin adapted to rotate freely in the aperture of the driving member, a metallic body of low magnetic retentivity connected rigidly to the pin capturing the driving member between itself and the pin head and presenting a smooth face away from the pin head and captured driving member, a driven member, and a permanent magnet connected to the driven member so as to present a channeled face to the smooth face of the metallic body and having a recess for accommodating so much of the pin as will allow contact between the faces.

CLARENCE JOHNSON.

No references cited. 

